A novel and potentially unrivalled meta-analysis of global food production cycles and their environmental impacts around the world may serve as a critical resource for policymakers, food producers and consumers alike, helping reveal data-supported opportunities to reduce food's impact on the environment. More than 570 million farms produce crops in almost all the world's climates and soils, causing the degradation of ecosystems, the depletion of water resources and exacerbation of climate change. It's challenging to find mitigation tactics that are effective for all producers; one only needs to enter a grocery store to recognize the sheer diversity of products, behind each of which there are a plethora of producers and manufacturing methods. Joseph Poore and Thomas Nemecek analyzed 570 studies of life cycle assessment (which tracks environmental impacts associated with all the stages of a product's life) that represent over 38,000 farms and 1,600 processors, packaging types and retailors in 123 countries. They quantified an unprecedented number of environmental impacts - greenhouse gas emissions (GHG), land use, water use, ocean acidification and eutrophication - of 40 different food products. They found that environmental impacts substantially varied among and within different products and producers, and that some products disproportionally skewed impact more than others. Importantly, the dataset also revealed potential trade-offs of impact-reducing efforts (for example, for already low-emission Northern European barley farms, reducing land use would actually increase GHG emissions per kilogram of grain). Navigating around these trade-offs, the researchers identified viable mitigation strategies, recommending that: producers monitor their impacts, choose from multiple practices that fit best with their locale and communicate impacts up the supply chain; policymakers incentivize environmental targets for producers; and consumers make informed dietary choices.
###
Science